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Multiferroic materials with good magneto-electric coupling are of great interest due to their enormous applications in the field of spintronic devices. Magnetoelectric (ME) gallium ferrite is an interesting material due to its room temperature (RT) piezoelectricity and near RT ferrimagnetism along with significant ME coupling (10−11 s/m at 4.2 K). The work aims to increase the magnetic transition temperature (TC) of the material above RT so that the material can have strong ME coupling at room temperature and can be implemented for practical applications. Several earlier reports have shown the magnetic transition temperature of Ga2−xFexO3 increases with higher Fe contents. Hence, we chose to study the properties of Ga2−xFexO3 (GFO) only for x = 1.2. Y3Fe5O12 (YIG) is another material that is RT ferromagnet material with very high resistivity (∼1012 Ω cm). In this work, by forming a GFO-YIG composite with only a 10% concentration of YIG, the phase transition temperature is increased beyond room temperature from ∼289 K for GFO to ∼309 K for 0.9 GFO-0.1 YIG. The remnant magnetization is also enhanced from 0.211 emu/g to 2.82 emu/g reporting a magnetization of ∼8.2 emu/g at 30 kOe.

Abstract Severe surface photocarrier recombination and poor electronic conductivity are the major factors behind the sluggish photoelectrochemical water oxidation kinetics of the ZnFe2O4 photoanode. Here, the CeOx catalyst overlayer has been coupled with the reduced ZnFe2O4 nanorods (NRs) to reduce the surface charge recombination on the photoanode significantly. The density functional theory (DFT) studies indicate that the oxygen vacancy defect‐rich CeOx catalyst constructs a favorable band alignment with ZnFe2O4 promoting rapid photocarrier separation and serves as a conducting photocarrier transfer pathway accelerating the hole transportation toward the electrode/electrolyte interface. The ZnFe2O4/CeOx nano‐heterostructure photoanode exhibits a current density of 0.64 mA cm−2 at 1.23 V versus RHE under AM 1.5 G illumination, which corresponds to >167% increase over that of the ZnFe2O4 NRs photoanode. The CeOx coupling reduces the onset potential cathodically by 180 mV over the ZnFe2O4 NRs photoanode. The ZnFe2O4/CeOx nano‐heterostructure photoanode also exhibits excellent charge transfer efficiency (≈64% at 1.23 V vs RHE) and photostability. The results indicate the superior catalytic performance of oxygen vacancy defect‐rich CeOx in the PEC process. This work demonstrates the multifunctional role of CeOx as a surface passivation overlayer, hole transfer layer, and efficient oxygen evolution reaction catalyst.

Herein, we report an unprecedented bilirubin (BR) adsorption efficiency of CoFe2O4 (CFO) nanostructures in contrast to the commercially available activated carbon and resin which are generally used for haemoperfusion and haemodialysis. We have synthesized CFO nanoparticles of diameter 100 nm and a series of nano-hollow spheres of diameter 100, 160, 250, and 350 nm using a simple template free solvothermal technique through proper variation of reaction time and capping agent, oleylamine (OLA), respectively, and carried out SiO2 coating by employing Stöber method. The comparative BR adsorption study of CFO and SiO2 coated CFO nanostructures indicates that apart from porosity and hollow configuration of nanostructures, the electrostatic affinity between anionic carboxyl group of BR and cationic amine group of OLA plays a significant role in adsorbing BR. Finally, we demonstrate that the BR adsorption capacity of the nanostructures can be tailored by varying the morphology as well as size of the nanostructures. We believe that our developed magnetic nanostructures could be considered as a potential material towards therapeutic applications against hyperbilirubinemia.

Multiferroic materials having good magneto-electric coupling are of great interest due to their enormous variety of applications in the field of spintronic devices. Despite having good magneto-electric coupling and multiferroic properties, gallium ferrite (GaFeO3) is plagued for having a very high leakage current compared to other multiferroic materials, which shadows the possibility of its application in device fabrication. The conduction mechanism behind this exceptionally high leakage current in GaFeO3 is still not identified properly. Here, we have carefully investigated the variation of leakage conduction with the change in morphologies, especially at the grain boundaries due to heat treatment temperature during sample preparation. A connected conductive network is detected along the fused grain boundaries, which provides the pathway for the leakage electrons to propagate through the material. Interestingly, the conductive atomic force microscopy image shows that oxygen vacancies at the near grain boundaries produce poor conductive regions. Small polaron hopping could be an effective transport mechanism present in the conductive ridges at the grain boundaries. Therefore, modification of grain boundaries could produce more effective results for the reduction in leakage current of GaFeO3. [ABSTRACT FROM AUTHOR]

The effective utilization of abundant visible solar light for photoelectrochemical water splitting is a green approach for energy harvesting, to reduce the enormous rise of carbon content in the atmosphere. Here, a novel efficient design strategy for p–n type nano-heterojunction photoanodes is demonstrated, with the goal of improving water splitting efficiency by growing low band gap p-CuFeO2 nanolayers on n-ZnO nanorods by an easy and scalable electrochemical route. The photoconversion efficiency of p–n CuFeO2/ZnO photoanodes is found to be ∼450% higher than that of pristine ZnO nanorod electrodes under visible solar light illumination (λ > 420 nm, intensity 10 mW cm−2). The p–n CuFeO2/ZnO nano-engineering not only boosts the visible light absorption but also resolves limitations regarding effective charge carrier separation and transportation due to interfacial band alignment. This photoanode also shows remarkably enhanced stability, where the formation of p–n nano-heterojunction enhances the easy migration of holes to the electrode/electrolyte interface, and of electrons to the counter electrode (Pt) for hydrogen generation. Therefore, this work demonstrates that p–n nano-engineering is a potential strategy to design light-harvesting electrodes for water splitting and clean energy generation. [ABSTRACT FROM AUTHOR]

Herein, we investigate the origin of enhanced absorption and complex conductivity of magnetite (Fe3O4) nano-hollow spheres (NHSs) in contrast to its nanoparticles (NPs) configuration in the frequency range 0.4–2.0 THz. The maximum absorption for NHSs and NPs of the same average diameter (~100 nm) are found to be 246.27 and 48.35 cm−1 at 1.8 THz, respectively. A detailed study suggests that the multiple resonance peaks in the absorption spectra are due to low frequency acoustic vibrational phonon modes of Fe3O4 nanostructures. Moreover, we demonstrate that the magnitude of total absorption can be tailored by varying the shell thickness of NHSs. It is found to increase with increasing shell thickness, and attain a maximum value of 498.5 cm−1 for the NHSs of average diameter 350 nm at 1.8 THz. The invariance of frequency dependent magnetic permeability points out that the absorption is basically due to dielectric loss instead of magnetic loss. The enhanced THz conductivity of Fe3O4 NHSs, as compared to NPs is described in light of thermally activated polaronic hopping which is found to increase with increasing THz absorption. Finally, the size dependent THz conductivity of NHSs confirms its sole dependence on the magnitude of THz absorptivity. [ABSTRACT FROM AUTHOR]

BackgroundInventorization and promotion of traditionally used local flora can be a better option to gain a wide range of alternative edible resources and multiple nutritional benefits. A perusal of literature highlighted the poor nutritional status of the tribal community living in eastern India and pointed out the potential lack of information regarding locally available wild edible resources.ObjectivePresent study aimed to document detailed information on wild edibles of eastern India, evaluate their cultural significance, and understand their role in achieving food security for the local tribes.Materials and methodologyTraditional knowledge of wild edibles was collected using a semi-structured questionnaire. Standard protocols were followed for collecting data. The collected data were analyzed using specific statistical tools like Relative frequency of citation (RFC), and Cultural food significance index (CFSI) to identify the most cited and culturally significant species. Jaccard similarity index (JI) was used to check the similarity of food plant use in different localities and adjoining areas of the laterite region in eastern India.ResultsA total of 2,603 citations were made by the 153 participants for 83 types of wild edibles spread across 48 families. Among the 83 species, 65 species were angiosperms, three species were pteridophytes and the rest 15 were from fungal groups. The RFC value ranged from 0.04 to 0.76, and Madhuca longifolia (L.) J.F.Macbr. was identified as the most frequently cited species (FC = 116; RFC = 0.76). The Cultural food significance index (CFSI) value varied from 0.2 to 844, and thirteen wild edibles like Colocasia esculenta (L.) Schott, Enydra fluctuans Lour., Marsilea vestita Hook. & Grev., Termitomyces heimii Natarajan, etc. were identified as culturally most important in the locality.ConclusionPresent study concludes that the local flora and macrofungi diversity is a treasure trove for fulfilling human hunger and gaining enough nutritional benefit. Scientific and sustainable utilization of these wild edibles can be a wise step to attain multiple health benefits and food security for the tribal community of eastern India. Moreover, culturally accepted species can be opted as a good source for bioprospecting nutraceuticals.

Livestock is the main backbone of the rural economy of an agriculture-based country like India. To mitigate the economic loss due to livestock’s poor performance and illness, folk phytotherapy for livestock healthcare is still actively practiced in India. Literature survey revealed that the laterite region of eastern India, characterized by its cultural, ethnic, and biological diversities, as well as topographical uniqueness, lacks comprehensive information on ethnoveterinary medicinal knowledge. The objective of the present study includes documentation of traditional knowledge of ethnoveterinary medicine (EVM) from the northern laterite region in eastern India. Ethnoveterinary medicinal data were collected using a semi-structured questionnaire, free listing, and focus group discussions. The factor for informants’ consensus (Fic), fidelity level (FL), and cultural value (CV) index have been employed for quantitative analyses. Jaccard index (JI) was used to check the knowledge similarity. Altogether, 1,234 citations were made by 132 participants. In total, 232 recorded ethnomedicinal species are used for preparing 306 remedies to treat 79 health disorders of livestock. Recorded species are distributed in 92 families, and Fabaceae is identified as the most medicinally diversified. Uses of 24 angiospermic taxa, one pteridophyte, and two fungal species were exclusively new to the existing inventory of Indian traditional ethnoveterinary medicine. In 20 disease categories, the informant consensus (Fic) value ranges from 0.4 to 0.83. According to the FL value and use-mention factor, 23 EVM plants have been identified as the most important species in the respective disease categories. Value of CV index highlighted nine species as culturally most significant (CV ≥ 0.0025 and frequency of citation ≥20) in the laterite region of eastern India. A large extent of recorded data are quite worthy for the Indian folk veterinary medicinal repository. A handful of new data reported here and statistically justified culturally most significant species will provide the golden opportunity for bioprospecting research.